Logic Error

[C# newbie with big problems]

Ok, I am building a product configurator which works quite well except
for a few bugs. It has a couple of listboxes and a checked list box.
Now the checked list box holds upgrades for products listed in a
different listbox and these upgrades are grouped by category so for
example if you select a computer then the checked list box may display:

512 RAM
1GB RAM
HDD 30 GB
HDD 60 GB
video...
so, these products are in logical groupings... RAM, HDD, etc. When I
select the checkbox for 1GB RAM then I want to get rid of the checkbox
on 512 RAM and here is where I run into my problem. I decided to give
each member of a group an identifier. Then I created an
ItemCheckChanged event handler. When one of the checks changes I change
all the other checks associated with this group which in turn changes
all the other cheks associated with this group which in turn changes...
you get the idea. This recursive loop never ends and I cant seem to get
the logic working any other way. Any Suggestions on how to fix my
problem? I dont care if there is another type of listbox that may help
or some way to stop logging the remainder of the check changes or even
comming up with some sort of dynamic radio button group thing (because
different items may have different amounts of upgrades and radio
buttons are what I really need here anyway)

thanx
--Roman

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

You do not use checkboxes for this kind of situation but RadioButtons.
--
--
Ignacio Machin,
ignacio.machin AT dot.state.fl.us
Florida Department Of Transportation

[Tom Spink]

C# newbie with big problems wrote:

Ok, I am building a product configurator which works quite well except
for a few bugs. It has a couple of listboxes and a checked list box.
Now the checked list box holds upgrades for products listed in a
different listbox and these upgrades are grouped by category so for
example if you select a computer then the checked list box may display:

512 RAM
1GB RAM
HDD 30 GB
HDD 60 GB
video...
so, these products are in logical groupings... RAM, HDD, etc. When I
select the checkbox for 1GB RAM then I want to get rid of the checkbox
on 512 RAM and here is where I run into my problem. I decided to give
each member of a group an identifier. Then I created an
ItemCheckChanged event handler. When one of the checks changes I change
all the other checks associated with this group which in turn changes
all the other cheks associated with this group which in turn changes...
you get the idea. This recursive loop never ends and I cant seem to get
the logic working any other way. Any Suggestions on how to fix my
problem? I dont care if there is another type of listbox that may help
or some way to stop logging the remainder of the check changes or even
comming up with some sort of dynamic radio button group thing (because
different items may have different amounts of upgrades and radio
buttons are what I really need here anyway)

thanx
--Roman

Hi Roman,

You could use a flag to indicate that the check is changing:

///
private bool _checkChanging;
private void OnCheckChanged ( object sender, EventArgs e )
{
if ( _checkChanging )
return;

_checkChanging = true;

try
{
// Do Your Processing
}
finally
{
_checkChanging = false;
}
}
///
--
Hope this helps,
Tom Spink

[C# newbie with big problems]

Right that would be great except I dont need just one group of radio
buttons, I need a dynamic amount of radio buttons, with multiple
groupings of dynamic size, which will change as soon as a new product
is selected, all in one ListBox looking object. I would happily switch
over to this if anything of the type was available. The only
checkedListBox thingy I could find is the CheckedListBox which doesn't
come in the radio button flavor... unless of course there is a class
library download that I am missing. I am not familiar enough with C# to
know what else is available that might solve my problem but would
appreciate any help

--Roman

[C# newbie with big problems]

Tom Spink wrote:

C# newbie with big problems wrote:

Ok, I am building a product configurator which works quite well except
for a few bugs. It has a couple of listboxes and a checked list box.
Now the checked list box holds upgrades for products listed in a
different listbox and these upgrades are grouped by category so for
example if you select a computer then the checked list box may display:

512 RAM
1GB RAM
HDD 30 GB
HDD 60 GB
video...
so, these products are in logical groupings... RAM, HDD, etc. When I
select the checkbox for 1GB RAM then I want to get rid of the checkbox
on 512 RAM and here is where I run into my problem. I decided to give
each member of a group an identifier. Then I created an
ItemCheckChanged event handler. When one of the checks changes I change
all the other checks associated with this group which in turn changes
all the other cheks associated with this group which in turn changes...
you get the idea. This recursive loop never ends and I cant seem to get
the logic working any other way. Any Suggestions on how to fix my
problem? I dont care if there is another type of listbox that may help
or some way to stop logging the remainder of the check changes or even
comming up with some sort of dynamic radio button group thing (because
different items may have different amounts of upgrades and radio
buttons are what I really need here anyway)

thanx
--Roman

Hi Roman,

You could use a flag to indicate that the check is changing:

///
private bool _checkChanging;
private void OnCheckChanged ( object sender, EventArgs e )
{
if ( _checkChanging )
return;

_checkChanging = true;

try
{
// Do Your Processing
}
finally
{
_checkChanging = false;
}
}
///
--
Hope this helps,
Tom Spink

Im not sure that would do me either tom... It seems to me that as soon
as the check changes it will launch the check changed event which will
launch the check changed event and so on... Im starting to think I need
a different way to approach this issue, unless there is a way to stop
logging that the check changes for the second time

[Tom Spink]

C# newbie with big problems wrote:

>
Tom Spink wrote:

>C# newbie with big problems wrote:

Ok, I am building a product configurator which works quite well except
for a few bugs. It has a couple of listboxes and a checked list box.
Now the checked list box holds upgrades for products listed in a
different listbox and these upgrades are grouped by category so for
example if you select a computer then the checked list box may display:

512 RAM
1GB RAM
HDD 30 GB
HDD 60 GB
video...
so, these products are in logical groupings... RAM, HDD, etc. When I
select the checkbox for 1GB RAM then I want to get rid of the checkbox
on 512 RAM and here is where I run into my problem. I decided to give
each member of a group an identifier. Then I created an
ItemCheckChanged event handler. When one of the checks changes I change
all the other checks associated with this group which in turn changes
all the other cheks associated with this group which in turn changes...
you get the idea. This recursive loop never ends and I cant seem to get
the logic working any other way. Any Suggestions on how to fix my
problem? I dont care if there is another type of listbox that may help
or some way to stop logging the remainder of the check changes or even
comming up with some sort of dynamic radio button group thing (because
different items may have different amounts of upgrades and radio
buttons are what I really need here anyway)

thanx
--Roman

Hi Roman,

You could use a flag to indicate that the check is changing:

///
private bool _checkChanging;
private void OnCheckChanged ( object sender, EventArgs e )
{
if ( _checkChanging )
return;

_checkChanging = true;

try
{
// Do Your Processing
}
finally
{
_checkChanging = false;
}
}
///
--
Hope this helps,
Tom Spink

Im not sure that would do me either tom... It seems to me that as soon
as the check changes it will launch the check changed event which will
launch the check changed event and so on... Im starting to think I need
a different way to approach this issue, unless there is a way to stop
logging that the check changes for the second time

Have you tried it? Perhaps I didn't explain the code clearly. If you
change the check inside the 'try...finally' block then it doesn't matter if
the event is fired... because the condition at the top of the method will
be satisfied, and the method will stop executing. If it stops executing at
that point, then it will no longer attempt to change the check, and so not
call the 'CheckChanged' event.

The model I've implemented above is designed to stop a method from executing
if it's already executing.

Try it, if you don't believe me!

--
Hope this helps,
Tom Spink

[C# newbie with big problems]

sorry tom... took me a while to get back to this. Yes that worked
great.. thanx alot

--Roman